Makkot 29
אמרו לו אמרת אמר להו לא אמר רבה האלהים אמרה וכתיבא ותנינא כתיבא (במדבר ה, ב) וישלחו מן המחנה [וגו'] ולא יטמאו את מחניהם תנינא הבא למקדש טמא
They asked him [Rebbi Yochanon] Did you say this? [that any prohibition preceded by a positive commandment is subject to flogging i.e. a lo saseah s'kedmu asseah]... He responded to them, No. [I retract what I said.] Rabbah said, By God! He said it. And it is backed by a posuk [verse] and a mishnah. It is written (Numbers 5,2) "And they shall send forth from the camp. etc. And they shall not defile their camps" [which is a lo saseah s'kedmu asseah] and it was taught in a mishna "One who enters the temple whilst impure [receives lashes].
אלא מאי טעמא קא הדר ביה משום דקשיא ליה אונס דתניא אונס שגירש אם ישראל הוא מחזיר ואינו לוקה אם כהן הוא לוקה ואינו מחזיר
So rather, what is the reason that [Rebbi Yochanon] retracted [his veiw]? Because he found [his veiw point] problematic with the case of a rapist [Ohneis] For it was taught in a barasiah An Ohneis who divorced his wife [in violation of the Torah's commandment], If he is a Yisroel [i.e. a non-Kohen] he takes her back and does not receive malkus. If he is a Kohen, he receives malkus and doesn't take her back.
אם ישראל הוא מחזיר ואינו לוקה אמאי לא תעשה שקדמו עשה הוא ולילקי
If he is a Yisroel he takes her back and doesn't receive malkus? Why? This is a case of a lo saseh sh'kadmu asseh, and [according to Rebbi Yochanon's origanl ruling] he should get malkus.
אמר עולא לא יאמר לו תהיה לאשה באונס וליגמר ממוציא שם רע ומה מוציא שם רע שלא עשה מעשה אמר רחמנא (דברים כב, יט) ולו תהיה לאשה אונס לא כל שכן
Ullah said [a possible resolution] [The Torah] need not have said "she should be to him for a wife" by Oneis, and it could have been derived from Motzei Shem Rah. And if by the case of Motzei Shem Rah where no action was performed, the Torah says (Deutermany 22,19) "She should be to him for a wife", then by Oneis [which does involve an action] is it not even more so?
ואכתי אונס ממוציא שם רע לא גמר דאיכא למיפרך מה למוציא שם רע שכן לוקה ומשלם
But still Oneis from Motzei Shem Rah can not be derived as you could ask on it, What comparison can be made to Motzei Shem Rah which has [a more stringent punishment of] malkus and a monetary payment?
אלא לא יאמר לו תהיה לאשה במוציא שם רע וליגמר מאונס ומה אונס שאינו לוקה ומשלם אמר רחמנא ולו תהיה לאשה מוציא שם רע לא כל שכן ולמה נאמר אם אינו ענין למוציא שם רע תנהו ענין לאונס אם אינו ענין לפניו תנהו ענין לאחריו
So rather "she shall be to him for a wife" should not have been stated by Motzei Shem Rah, and it could have been derived from Oneis. If by Oneis which doesn't have [the double punishment] of malkus and monetary payment, the Torah says, "she shall be to him for a wife", then is not Motzei Shem Rah even more so? Why then is it repeated [by Motzei Shem Rah, if it can just be derived from Oneis]? If it is not needed to teach us anything by Motzei Shem Rah, then apply this commandment by Oneis. If it is not needed before [he divorces her], apply it afterwards.
אלא לא יאמר לו תהיה לאשה במוציא שם רע שהרי אשתו היא למה נאמר אם אינו ענין למוציא שם רע תנהו ענין לאונס ואם אינו ענין לפניו תנהו ענין לאחריו
So rather "she shall be to him for a wife" should not have been stated with regards to Motzei Shem Rah, because she is already his wife. Why then was it said? If it is not needed to teach us anything by Motzei Shem Rah, then apply this commandment by Oneis. If it is not needed before [he divorces her], apply it afterwards.
ואימא ואם אינו ענין לפניו דמוציא שם רע תנהו ענין לאחריו דידיה דלא לקי
But you can say, If it is not applicable before the Motzei Shem Rah [divorces his wife] apply it afterwards by itself [Motzei Shem Rah] that he does not recieve malkus for divorcing his wife [because he can remarry her].
אין הכי נמי ואתי אונס וגמר מיניה במאי גמר מיניה אי בקל וחומר אי במה מצינו איכא למיפרך (כדפרכינן) מה למוציא שם רע שכן לא עשה מעשה
Yes this is imndeed so, but Oneis comes and is derived from this. With what is it derived? Whether by a Kal V'chomer or by a Mah Matzhino, I can ask as I have previosly asked, what comparison can be made to Motzei Shem Rah which [is less] as it involves no action?
אלא אמר רבא כל ימיו בעמוד והחזר וכן כי אתא רבין א"ר יוחנן כל ימיו בעמוד והחזר
Rather Rava said "all his days" is a commandment to take her back. And similirly when Ravan came he said in the name of Rebbi Yochanon, "all his days" is a commandment to take her back.
א"ל רב פפא לרבא והא לא דמי לאויה ללאו דחסימה א"ל משום דכתב ביה רחמנא עשה יתירא מגרע גרע
Rav Pappa said to Rava But [a lo saseh sh'kedmu asseh] is not similar to the prohibition of muzzling, [so how can Rebbi Yochanon rule that one receives malkus]? Rava answered him, Just because the Torah writes by it an additional commandment, does that make it any less stringent?!
אי הכי לאו שניתק לעשה נמי לימא משום דכתב ביה רחמנא עשה יתירא מגרע גרע א"ל ההוא לנתוקי לאו הוא דאתא
If so [that an extra commandment shouldn't detract from it, then the same argument can be made by] a lav sh'nituk l'asseh also, say that just because the Torah writes by it an extra commandment, does that make it any less stringent?! Rava explained [the differnece] to him, That one [by a lav sh'nituk l'asseh the commandment] is coming to remove the prohibition.